1. Field
Apparatuses and methods consistent with exemplary embodiments relate to an apparatus for removing a transmission leakage signal from a radio frequency identification (RFID) reader.
2. Description of the Related Art
RFID is a wireless recognition technology for acquiring information regarding an object to be identified through communication between a tag attached to the object and a reader, and is a base for a next-generation ubiquitous sensor network (USN).
An RFID system includes a tag storing information regarding an object and a reader acquiring the information, and uses the same frequency, unlike other wireless communication systems which use different transmission/reception frequencies. Thus, separation between transmission and reception signal ports is important to the RFID system. Insufficient separation of a transmission signal and a reception signal deteriorates identification perception of the reader.
Antennas are conventionally separated in order to improve separation between transmission and reception signals. However, if a plurality of antennas are used to separate the two signals, a space where the antennas are installed, the size of a transceiver, and manufacturing costs are increased.
In order to address this problem, one antenna is used for both transmitting and receiving signals, together with a circulator or a directional coupler that separates transmission signals from reception signals. However, the circulator or the directional coupler is not an ideal device, and use of such device may cause a leakage of a transmission signal when the transmission signal enters a receiving path.